<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div style="border: 1px solid #8ff599">标签1</div>
<!--html中定义css-‘style’：边框1像素-实线-颜色-->
<div>标签2</div>

<span style="border: 1px solid #8ff599">标签1</span>
<span>标签2</span>
<!--div为一整列，span为输出长度-->

<p>段落1</p>
<p>段落2</p>
</body>
</html>